fix: content-disposition header parsing

lib/client.js

@@ -4,6 +4,7 @@
 
 const assert = require('assert')
 const net = require('net')
+const transcode = require('buffer').transcode
 const util = require('./core/util')
 const timers = require('./timers')
 const Request = require('./core/request')
@@ -618,6 +619,11 @@ class Parser {
       this.connection += buf.toString()
     } else if (key.length === 14 && key.toString().toLowerCase() === 'content-length') {
       this.contentLength += buf.toString()
+    } else if (key.length === 19 && key.toString().toLowerCase() === 'content-disposition') {
+      // https://www.rfc-editor.org/rfc/rfc6266#section-4.3
+      // we need to recieve the buffer as latin1
+      // so it would not transform to utf-8 wrongly
+      this.headers[len - 1] = transcode(buf, 'latin1', 'utf8')
     }
 
     this.trackHeader(buf.length)

test/issue-1903.js

@@ -0,0 +1,78 @@
+'use strict'
+
+const { createServer } = require('node:http')
+const { test } = require('tap')
+const { request } = require('..')
+
+function createPromise() {
+  const result = {}
+  result.promise = new Promise((resolve) => {
+    result.resolve = resolve
+  })
+  return result
+}
+
+test('should parse content-disposition consistencely', async (t) => {
+  t.plan(5)
+
+  // create promise to allow server spinup in parallel
+  const spinup1 = createPromise()
+  const spinup2 = createPromise()
+  const spinup3 = createPromise()
+
+  // variables to store content-disposition header
+  const header = []
+
+  const server = createServer((req, res) => {
+    res.writeHead(200, {
+      'content-length': 2,
+      'content-disposition': 'attachment; filename="år.pdf"'
+    })
+    header.push(header)
+    res.end('OK', spinup1.resolve)
+  })
+  t.teardown(server.close.bind(server))
+  server.listen(0, spinup1.resolve)
+
+  const proxy1 = createServer(async (req, res) => {
+    const { statusCode, headers, body } = await request(`http://localhost:${server.address().port}`, {
+      method: "GET"
+    })
+    header.push(headers['content-disposition'])
+    delete headers['transfer-encoding']
+    res.writeHead(statusCode, headers)
+    body.pipe(res)
+  })
+  t.teardown(proxy1.close.bind(proxy1))
+  proxy1.listen(0, spinup2.resolve)
+
+  const proxy2 = createServer(async (req, res) => {
+    const { statusCode, headers, body } = await request(`http://localhost:${proxy1.address().port}`, {
+      method: "GET"
+    })
+    header.push(headers['content-disposition'])
+    delete headers['transfer-encoding']
+    res.writeHead(statusCode, headers)
+    body.pipe(res)
+  })
+  t.teardown(proxy2.close.bind(proxy2))
+  proxy2.listen(0, spinup3.resolve)
+
+  // wait until all server spinup
+  await Promise.all([spinup1.promise, spinup2.promise, spinup3.promise])
+
+  const { statusCode, headers, body } = await request(`http://localhost:${proxy2.address().port}`, {
+    method: "GET"
+  })
+  header.push(headers['content-disposition'])
+  t.equal(statusCode, 200)
+  t.equal(await body.text(), 'OK')
+
+  // we check header
+  // must not be the same in first proxy
+  t.notSame(header[0], header[1])
+  // chaining always the same value
+  t.equal(header[1], header[2])
+  t.equal(header[2], header[3])
+})
+